Adjustable taper bit.



C. R. HANNAH.

ADJUSTABLE TAPER BIT. APPLICATION FILED Nov. 30, 1914.

Patented Jan. 16, 1917.

UNITE@ STATES FATENT CYRIL R. HANNAI-I, OF ANAHEIM, CALIFORNIA, ASSIGNOR OF ONE-HALF T0 C. IVI. BAUMGARDNER, 0F ANAHEIM, CALIFORNIA.

ADJUSTABLE TAPER BIT.

Specification of Letters Patent.

Patented Jan. 16, 191'?.

Application led November 30, 1914. Y Serial No. 874,610.

To all whom t may concern:

Be it known that I, CYRIL R. HANivAH, a citizen of the United States, residing at Anaheim, in the county of Orange and State of California, have invented a new and useful Adjustable Taper Bit, of wh1ch the following is a specification.

This invention comprehends improvements in adjustable taper bits having selffeeding taper forming blades, and the primary object is to provide a bit of this type which shall be of extremely simple, practical and durable construction. f

Another object of the invention resides 1n the provision of a taper forming bit which may be adjusted to cut either a hole of gradually increasing diameter or one of gradually decreasing diameter.

The invention also aims to generally 1mprove devices of this nature to render them more useful and more commercially desirable.

With these and other objects in view, the invention consists in certain features of construction, combination and arrangement of parts as will be hereinafter described, illustrated and claimed. Y

Referring to the drawings: Figure 1 i s a side elevation of my improved taper forming bit. Fig. 2 is-a top plan view of the bit. Fig. 3 is a longitudinal sectional view partly in elevation. Fig. 1- is a view similar to Fig. 3, showing a modified form of bit. Fig. 5 is a vertical elevation showing the bit in position within a hole, which has been formed therewith. Fig. 6 is a side elevation of a taper forming blade which is intended primarily for cutting holes of gradually decreasing diameter. Fig. 7 is a side elevation of a taper forming blade designed to cut holes of a gradually increasing diameter.

Referring in detail to the drawings by numerals,1 designates a bit having the end of its shank enlarged as at 2, and said enlargement carrying on its `free terminal the customary boring and feeding spiral 3.

In carrying out my invention, I preferably form the flat. face'of the enlargement 2 with a recess 4: to receive a disk 5, which is pivotally secured by a screw 6. This disk carries the taper forming blade 7, which may be locked against longitudinal movement by a screw 8, said screw engaging the top of the blade flange 9, as best shown in Fig. 3. As the bit is longer than the diameter of the block or disk 5, it is necessary in order that the blade may turn, to form the outwardly flaring recesses 10 in the flat face of the enlargement 2. These recesses communicate with the circular recess 4, and are directly opposed to each other.

The blade 7 is formed with a cutting edge 11 and with a cutting and feeding lip 12. The end 13 of this blade'eXtends preferably at right angles to the side edges thereof, and it is the inclination to the longitudinal axis of the bit at which this end is set that determines the taper formed by the tool.

vWhen the blade is positioned so that the end 13 yis parallel with the longitudinal axis of the bit, the cutting blade 7 will form a cylindrical opening, and it is necessary to secure the blade against movement relative to the block 5 when so positioned.

`When the blade is adjusted, as shown in Fig. 5, so the oblique end 13 is inclined inwardly with respect to the cutting end of the bit, a hole of gradually decreasing diameter will be cut, provided, of course, that the blade is left free to slide through the block 5. In starting a hole of this formation, the blade 7 is drawn outwardly until the end l3'is spaced from the longitudinal center of the bit a distance equal to the largest diameter of the opening desired. This position is indicated in Fig. 5 by the dotted lines. The screw 8 is then turned for temporarily holding the blade against sliding so that the cutting lip may cut a true circle at the beginning of the operation for starting the blade properly. The screw 8 is then turned reversely to release the blade and, upon the continued rotation of the bit the blade will be free to take its own course and slide radially as the hole being bored `diminishes in diameter. The lip 12 is of sufficient length to hold the bit to its course and prevent its deflection by the fibers of the wood during the boring action after the first circular groove has been formed while the blade is held against sliding, as above described.

The bevel face 14 of the lip 12'tends always to feed the blade outwardly, but when the guiding end 13 is inclined, as shown in Fig. 5, said end will overcome the outward pressure of the face 12 and cause the blade to work inwardly and reduce gradually the opening, and the inclination of this end 13 to the axis of the bit determines the speed atwhich the blade feeds inwardly i or, in other words, determines the degree of taper. rlhe spiral 3 draws the tool through the wood, and forms a circular opening which is enlarged by the blade 7. j

If the block 5 is turned so that the end 13 of the blade 7 is inclined outwardly with respect to the cutting end of the tool, and the block locked by the screw 16, the blade will feed outwardly during its cutting action and form a hole of gradually increasing diameter. The opposite faces of the block 5 and recess 4 may be serrated as indicated at 15 so the screw 6 will be suiicient to hold the block in any adjusted position. Or if thought desirable, a lock screw 16 may be provided. The block 5 may be formed with a series of graduations 17 readable in conjunction with an indicator 18 so that the angle of the taper forming blade with respect to the longitudinal axis of the bit may be easily determined.

In Fig. 4 is shown a modified form of bit, wherein the block 5 is dispensed with and the taper forming blade 19 carried directly by the enlargement 20. The blade slides through a recess 21 formed in the enlargement 20, and is held therein by a plate 22 secured by a screw 23. In using this form of the device, it is necessary to have a plurality of taper forming blades in order to secure dierent tapered openings since the angle of the blades cannot be varied. The blade 24 shown in Fig. 6 when used with the bit illustrated in Fig. 4 will form an opening of gradually decreasing diameter since the end 25 is turned so as to force the blade gradually inwardly. The blade 26 illustrated in Fig. 7 will, because of its outwardly inclined guiding end 27, form, when used with the bit 4, an opening of gradually increasing diameter as will be clearly understood.

The inclination of the outer end of the blade in my device causes the formation of taper holes. Vhen the outer end is inclined upwardly and outwardly from theV lower end of the bit, as illustrated in Figs. 5 and (-3 in the drawings, the taper of the hole bored corresponds to the inclination of said end of the blade. When the blade is inclined upwardly and inwardly the taper of the opening formed will correspond to said upward and inward inclination of the blade. In using the blade which has its Vouter end upwardly and outwardly inclined, as illustrated in Figs. 5 and 6 in the drawings, for example, when the bit is turned the feeder causes the blade to advance into the wood and as the lower side of said bit is nearer to the vertical axis of the bit than the upper side of the bit at the outer end thereof, the inclined end face will engage the inclined face of the opening formed by the lip 12 and produce a cam action which can only tend to force the blade inwardly in view of the inclination of the blade and of the wall of the Vopening being formed. `The lip V12 when first engaged and caused to bite into the wood has a tendency to move outwardly radially relative to the bit but this is overcome by the outer face thereof engaging the wall of the cut made by the lip whenV the blade was primarily held secured while making the preliminary cut, as above described.

From the foregoing description taken in connection with the accompanying drawings, it will be seen that I have provided a very simple and practical taper forming bit. I, of course, do not wish to be limited to the form shown, but desire to have the privilege of making such changes as will fall within the scope and spirit of the appended claims.

What I claim is:

1. In a taper bit, a blade adjustable to different angles with respect tothe longitudinal center of the bit, said blade being freely movable radially of the bit and having a cutting and feeding lip adapted to engage at its outer face, the opening being bored and having said outer face inclined relative to the vertical axis of the bit.

2. In a boring tool, a shank, a blade mounted in said shank and freely movable in a substantially radial plane and having a surface arranged at an oblique angle to the axis of the shank and engaging the work for laterally moving the blade to progressively vary the diameter of the hole being bored.

3. In Va boring tool, a shank having feeding means on one end thereof, a blade freely radially movable upon said shank, and means carried by the blade and engaging the work to move the blade gradually to form a tapered opening.

4. In a boring tool, a shank, boring and feeding means on one end thereof, a blade freely movable radially of said shank and mounted angularly adjustably to provide for inclining one end thereof with reference to the axial line of the shank to vary the diameter of the opening being bored.

5. The combination with a bit,of a rotatable block pivotally secured thereto, a taper forming blade freely slidably carried by the block, and means for locking the block against movement. l

6. In a taper bit, a taper forming blade having one end oblique with reference to the side edges thereof,l a cutting and feeding lip adjacent said oblique end, the blade being freely movable transversely of the bit during operation, justing the blade relative to the bit, said blade arranged to have the feeding lip and oblique end engage the side of the opening being bored.

7. In a boringv tool, a shank having an 130 and means for angularly ad- V enlargement on one end thereof, a cutting and feeding spiral carried by the free terminal of said enlargement, a disk rotatably secured to said enlargement, a blade slidably carried by said disk, the blade being of greater length than the diameter of the disk, and means to lock the disk against rotation, one end of said blade to be disposed at an angle to the Vertical 'axis of the spiral and engage the side of the opening being bored. 8. In a taper bit, a blade slidable in operation transversely of and upon said bit, a

depending cutting and feeding lip carried at one end of said blade, and means to adjust said blade whereby said lip and the adjacent end of the blade may be disposed at an angle to the vertical axis of the bit.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 13th day of November, 1914.

CYRIL R. IIANNAH. In presence of- RoDNEY M. SMITH, LORRAINE E. DU'RRoW.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. G. 

